George m



@uiten `tutte strnt @Hire Letters Patent No. 69,236, dated September 24,1867.

IMPROVEMENT IN BURGLAR-PRDF WINDOW AND DOOR-GRATES.

. dtlgt dgehnle nicht' tu it tigen ttttttt ntent mth matting mit utilistante,

To ALL WHoM 1T MAY ooNcERN:

De it known that we, GEORGE M. MILLER and HERMANN MUNI), of the city ofChicago, county of Cook, and State of Illinois, have invented new anduseful Improvements in Burglar-Proof Window and Door-Gratesg and we dohereby declare that the following is a full and exact descriptionthereof, reference being had tothe accompanying drawings, making part ofthisspecication, in which' Figure 1 represents the inside view of awindowwith a grate in.

Figure 2, the top View of the grate and fixing.

Figure represents the case of the lock with its spring and its slide putinside.

Figure 4 represents the same case of the lock with a movable plateputin; und

Figure 5 represents the outside plate of the lock; and

Figure 6 represents the horizontal section of the latch and of the rodto which it is riveted. I

. Similar letters of reference indicate similar parts of thearrangement.

The nature of our invention consists in environ grate and a lock, soarranged that, `by a single turn of key,

the grate muy be fastened to or loosened from a window, door, or otheropening, thus forming the burglar-proof grate in the night time, andleaving the opening unobstructed in the day time.

To enable others skilled in the art to make and use our invention, wewill proceed to describe its construction and operation.

A is an iron grate, the rod B of which has projections b b, which enterthe openings in the plates C C,

attached to the casing of the opening, the rod B turning with the latchD of the lock E, which latch is rivetcd to the rod B. Plates F F,fastened to the opposite easing, have jaws, into which enters the rod Gof the grate. The lock E -is put over the rod B on one side, and overthe rod next to it of the grate on the other side. Its

v mechanism consists of a spring,lm, the upper end of which buttsagainst the cornerof theplate n, said plate being movable. There is aslide, s, which shuts the key-hole when the grate is put in and locked.

The operation consists in the following: To unlock and loosen the gratethe key is turned, and, it moving the sliding-plate n, the notch of thelatch D becomes disengaged; and, by pressing the grate out, the latch Dand the rod B turn and disengage themselves from the casing. To lock the=grate it is put in, and the latch simply pressed into the lock, and thegrate is fastened.

What we claim as'our invent-ion, and desire to secure by Letters Patent,is

In combination with the window-frame or door, the grate A, plates F F.lock E, latch D, the whole arranged substantially as and for the purposeset forth.

GEORGE M. MILLER,

HERMANN MUND. Witnesses:

J. Bi..TUr.c111N, JAS. It. HAYDEN.

